gdb/symfile.h

   1 /* Definitions for reading symbol files into GDB.
   2
   3    Copyright (C) 1990-2013 Free Software Foundation, Inc.
   4
   5    This file is part of GDB.
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 3 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  19
  20 #if !defined (SYMFILE_H)
  21 #define SYMFILE_H
  22
  23 /* This file requires that you first include "bfd.h".  */
  24 #include "symtab.h"
  25 #include "probe.h"
  26
  27 /* Opaque declarations.  */
  28 struct target_section;
  29 struct objfile;
  30 struct obj_section;
  31 struct obstack;
  32 struct block;
  33 struct probe;
  34 struct value;
  35 struct frame_info;
  36 struct agent_expr;
  37 struct axs_value;
  38
  39 /* Comparison function for symbol look ups.  */
  40
  41 typedef int (symbol_compare_ftype) (const char *string1,
  42                                     const char *string2);
  43
  44 /* Partial symbols are stored in the psymbol_cache and pointers to
  45    them are kept in a dynamically grown array that is obtained from
  46    malloc and grown as necessary via realloc.  Each objfile typically
  47    has two of these, one for global symbols and one for static
  48    symbols.  Although this adds a level of indirection for storing or
  49    accessing the partial symbols, it allows us to throw away duplicate
  50    psymbols and set all pointers to the single saved instance.  */
  51
  52 struct psymbol_allocation_list
  53 {
  54
  55   /* Pointer to beginning of dynamically allocated array of pointers
  56      to partial symbols.  The array is dynamically expanded as
  57      necessary to accommodate more pointers.  */
  58
  59   struct partial_symbol **list;
  60
  61   /* Pointer to next available slot in which to store a pointer to a
  62      partial symbol.  */
  63
  64   struct partial_symbol **next;
  65
  66   /* Number of allocated pointer slots in current dynamic array (not
  67      the number of bytes of storage).  The "next" pointer will always
  68      point somewhere between list[0] and list[size], and when at
  69      list[size] the array will be expanded on the next attempt to
  70      store a pointer.  */
  71
  72   int size;
  73 };
  74
  75 /* Define an array of addresses to accommodate non-contiguous dynamic
  76    loading of modules.  This is for use when entering commands, so we
  77    can keep track of the section names until we read the file and can
  78    map them to bfd sections.  This structure is also used by solib.c
  79    to communicate the section addresses in shared objects to
  80    symbol_file_add ().  */
  81
  82 struct section_addr_info
  83 {
  84   /* The number of sections for which address information is
  85      available.  */
  86   size_t num_sections;
  87   /* Sections whose names are file format dependent.  */
  88   struct other_sections
  89   {
  90     CORE_ADDR addr;
  91     char *name;
  92
  93     /* SECTINDEX must be valid for associated BFD or set to -1.  */
  94     int sectindex;
  95   } other[1];
  96 };
  97
  98
  99 /* A table listing the load segments in a symfile, and which segment
 100    each BFD section belongs to.  */
 101 struct symfile_segment_data
 102 {
 103   /* How many segments are present in this file.  If there are
 104      two, the text segment is the first one and the data segment
 105      is the second one.  */
 106   int num_segments;
 107
 108   /* If NUM_SEGMENTS is greater than zero, the original base address
 109      of each segment.  */
 110   CORE_ADDR *segment_bases;
 111
 112   /* If NUM_SEGMENTS is greater than zero, the memory size of each
 113      segment.  */
 114   CORE_ADDR *segment_sizes;
 115
 116   /* If NUM_SEGMENTS is greater than zero, this is an array of entries
 117      recording which segment contains each BFD section.
 118      SEGMENT_INFO[I] is S+1 if the I'th BFD section belongs to segment
 119      S, or zero if it is not in any segment.  */
 120   int *segment_info;
 121 };
 122
 123 /* Callback for quick_symbol_functions->map_symbol_filenames.  */
 124
 125 typedef void (symbol_filename_ftype) (const char *filename,
 126                                       const char *fullname, void *data);
 127
 128 /* The "quick" symbol functions exist so that symbol readers can
 129    avoiding an initial read of all the symbols.  For example, symbol
 130    readers might choose to use the "partial symbol table" utilities,
 131    which is one implementation of the quick symbol functions.
 132
 133    The quick symbol functions are generally opaque: the underlying
 134    representation is hidden from the caller.
 135
 136    In general, these functions should only look at whatever special
 137    index the symbol reader creates -- looking through the symbol
 138    tables themselves is handled by generic code.  If a function is
 139    defined as returning a "symbol table", this means that the function
 140    should only return a newly-created symbol table; it should not
 141    examine pre-existing ones.
 142
 143    The exact list of functions here was determined in an ad hoc way
 144    based on gdb's history.  */
 145
 146 struct quick_symbol_functions
 147 {
 148   /* Return true if this objfile has any "partial" symbols
 149      available.  */
 150   int (*has_symbols) (struct objfile *objfile);
 151
 152   /* Return the symbol table for the "last" file appearing in
 153      OBJFILE.  */
 154   struct symtab *(*find_last_source_symtab) (struct objfile *objfile);
 155
 156   /* Forget all cached full file names for OBJFILE.  */
 157   void (*forget_cached_source_info) (struct objfile *objfile);
 158
 159   /* Expand and iterate over each "partial" symbol table in OBJFILE
 160      where the source file is named NAME.
 161
 162      If NAME is not absolute, a match after a '/' in the symbol table's
 163      file name will also work, REAL_PATH is NULL then.  If NAME is
 164      absolute then REAL_PATH is non-NULL absolute file name as resolved
 165      via gdb_realpath from NAME.
 166
 167      If a match is found, the "partial" symbol table is expanded.
 168      Then, this calls iterate_over_some_symtabs (or equivalent) over
 169      all newly-created symbol tables, passing CALLBACK and DATA to it.
 170      The result of this call is returned.  */
 171   int (*map_symtabs_matching_filename) (struct objfile *objfile,
 172                                         const char *name,
 173                                         const char *real_path,
 174                                         int (*callback) (struct symtab *,
 175                                                          void *),
 176                                         void *data);
 177
 178   /* Check to see if the symbol is defined in a "partial" symbol table
 179      of OBJFILE.  KIND should be either GLOBAL_BLOCK or STATIC_BLOCK,
 180      depending on whether we want to search global symbols or static
 181      symbols.  NAME is the name of the symbol to look for.  DOMAIN
 182      indicates what sort of symbol to search for.
 183
 184      Returns the newly-expanded symbol table in which the symbol is
 185      defined, or NULL if no such symbol table exists.  If OBJFILE
 186      contains !TYPE_OPAQUE symbol prefer its symtab.  If it contains
 187      only TYPE_OPAQUE symbol(s), return at least that symtab.  */
 188   struct symtab *(*lookup_symbol) (struct objfile *objfile,
 189                                    int kind, const char *name,
 190                                    domain_enum domain);
 191
 192   /* Print statistics about any indices loaded for OBJFILE.  The
 193      statistics should be printed to gdb_stdout.  This is used for
 194      "maint print statistics".  */
 195   void (*print_stats) (struct objfile *objfile);
 196
 197   /* Dump any indices loaded for OBJFILE.  The dump should go to
 198      gdb_stdout.  This is used for "maint print objfiles".  */
 199   void (*dump) (struct objfile *objfile);
 200
 201   /* This is called by objfile_relocate to relocate any indices loaded
 202      for OBJFILE.  */
 203   void (*relocate) (struct objfile *objfile,
 204                     const struct section_offsets *new_offsets,
 205                     const struct section_offsets *delta);
 206
 207   /* Find all the symbols in OBJFILE named FUNC_NAME, and ensure that
 208      the corresponding symbol tables are loaded.  */
 209   void (*expand_symtabs_for_function) (struct objfile *objfile,
 210                                        const char *func_name);
 211
 212   /* Read all symbol tables associated with OBJFILE.  */
 213   void (*expand_all_symtabs) (struct objfile *objfile);
 214
 215   /* Read all symbol tables associated with OBJFILE which have
 216      symtab_to_fullname equal to FULLNAME.
 217      This is for the purposes of examining code only, e.g., expand_line_sal.
 218      The routine may ignore debug info that is known to not be useful with
 219      code, e.g., DW_TAG_type_unit for dwarf debug info.  */
 220   void (*expand_symtabs_with_fullname) (struct objfile *objfile,
 221                                         const char *fullname);
 222
 223   /* Find global or static symbols in all tables that are in NAMESPACE
 224      and for which MATCH (symbol name, NAME) == 0, passing each to
 225      CALLBACK, reading in partial symbol tables as needed.  Look
 226      through global symbols if GLOBAL and otherwise static symbols.
 227      Passes NAME, NAMESPACE, and DATA to CALLBACK with each symbol
 228      found.  After each block is processed, passes NULL to CALLBACK.
 229      MATCH must be weaker than strcmp_iw_ordered in the sense that
 230      strcmp_iw_ordered(x,y) == 0 --> MATCH(x,y) == 0.  ORDERED_COMPARE,
 231      if non-null, must be an ordering relation compatible with
 232      strcmp_iw_ordered in the sense that
 233             strcmp_iw_ordered(x,y) == 0 --> ORDERED_COMPARE(x,y) == 0
 234      and
 235             strcmp_iw_ordered(x,y) <= 0 --> ORDERED_COMPARE(x,y) <= 0
 236      (allowing strcmp_iw_ordered(x,y) < 0 while ORDERED_COMPARE(x, y) == 0).
 237      CALLBACK returns 0 to indicate that the scan should continue, or
 238      non-zero to indicate that the scan should be terminated.  */
 239
 240   void (*map_matching_symbols) (struct objfile *,
 241                                 const char *name, domain_enum namespace,
 242                                 int global,
 243                                 int (*callback) (struct block *,
 244                                                  struct symbol *, void *),
 245                                 void *data,
 246                                 symbol_compare_ftype *match,
 247                                 symbol_compare_ftype *ordered_compare);
 248
 249   /* Expand all symbol tables in OBJFILE matching some criteria.
 250
 251      FILE_MATCHER is called for each file in OBJFILE.  The file name
 252      and the DATA argument are passed to it.  If it returns zero, this
 253      file is skipped.  If FILE_MATCHER is NULL such file is not skipped.
 254      If BASENAMES is non-zero the function should consider only base name of
 255      DATA (passed file name is already only the lbasename part).
 256
 257      Otherwise, if KIND does not match this symbol is skipped.
 258
 259      If even KIND matches, then NAME_MATCHER is called for each symbol
 260      defined in the file.  The symbol "search" name and DATA are passed
 261      to NAME_MATCHER.
 262
 263      If NAME_MATCHER returns zero, then this symbol is skipped.
 264
 265      Otherwise, this symbol's symbol table is expanded.
 266
 267      DATA is user data that is passed unmodified to the callback
 268      functions.  */
 269   void (*expand_symtabs_matching)
 270     (struct objfile *objfile,
 271      int (*file_matcher) (const char *, void *, int basenames),
 272      int (*name_matcher) (const char *, void *),
 273      enum search_domain kind,
 274      void *data);
 275
 276   /* Return the symbol table from OBJFILE that contains PC and
 277      SECTION.  Return NULL if there is no such symbol table.  This
 278      should return the symbol table that contains a symbol whose
 279      address exactly matches PC, or, if there is no exact match, the
 280      symbol table that contains a symbol whose address is closest to
 281      PC.  */
 282   struct symtab *(*find_pc_sect_symtab) (struct objfile *objfile,
 283                                          struct minimal_symbol *msymbol,
 284                                          CORE_ADDR pc,
 285                                          struct obj_section *section,
 286                                          int warn_if_readin);
 287
 288   /* Call a callback for every file defined in OBJFILE whose symtab is
 289      not already read in.  FUN is the callback.  It is passed the file's
 290      FILENAME, the file's FULLNAME (if need_fullname is non-zero), and
 291      the DATA passed to this function.  */
 292   void (*map_symbol_filenames) (struct objfile *objfile,
 293                                 symbol_filename_ftype *fun, void *data,
 294                                 int need_fullname);
 295 };
 296
 297 /* Structure of functions used for probe support.  If one of these functions
 298    is provided, all must be.  */
 299
 300 struct sym_probe_fns
 301 {
 302   /* If non-NULL, return an array of probe objects.
 303
 304      The returned value does not have to be freed and it has lifetime of the
 305      OBJFILE.  */
 306   VEC (probe_p) *(*sym_get_probes) (struct objfile *);
 307
 308   /* Return the number of arguments available to PROBE.  PROBE will
 309      have come from a call to this objfile's sym_get_probes method.
 310      If you provide an implementation of sym_get_probes, you must
 311      implement this method as well.  */
 312   unsigned (*sym_get_probe_argument_count) (struct probe *probe);
 313
 314   /* Return 1 if the probe interface can evaluate the arguments of probe
 315      PROBE, zero otherwise.  This function can be probe-specific, informing
 316      whether only the arguments of PROBE can be evaluated, of generic,
 317      informing whether the probe interface is able to evaluate any kind of
 318      argument.  If you provide an implementation of sym_get_probes, you must
 319      implement this method as well.  */
 320   int (*can_evaluate_probe_arguments) (struct probe *probe);
 321
 322   /* Evaluate the Nth argument available to PROBE.  PROBE will have
 323      come from a call to this objfile's sym_get_probes method.  N will
 324      be between 0 and the number of arguments available to this probe.
 325      FRAME is the frame in which the evaluation is done; the frame's
 326      PC will match the address of the probe.  If you provide an
 327      implementation of sym_get_probes, you must implement this method
 328      as well.  */
 329   struct value *(*sym_evaluate_probe_argument) (struct probe *probe,
 330                                                 unsigned n);
 331
 332   /* Compile the Nth probe argument to an agent expression.  PROBE
 333      will have come from a call to this objfile's sym_get_probes
 334      method.  N will be between 0 and the number of arguments
 335      available to this probe.  EXPR and VALUE are the agent expression
 336      that is being updated.  */
 337   void (*sym_compile_to_ax) (struct probe *probe,
 338                              struct agent_expr *expr,
 339                              struct axs_value *value,
 340                              unsigned n);
 341
 342   /* Relocate the probe section of OBJFILE.  */
 343   void (*sym_relocate_probe) (struct objfile *objfile,
 344                               const struct section_offsets *new_offsets,
 345                               const struct section_offsets *delta);
 346 };
 347
 348 /* Structure to keep track of symbol reading functions for various
 349    object file types.  */
 350
 351 struct sym_fns
 352 {
 353   /* Initializes anything that is global to the entire symbol table.
 354      It is called during symbol_file_add, when we begin debugging an
 355      entirely new program.  */
 356
 357   void (*sym_new_init) (struct objfile *);
 358
 359   /* Reads any initial information from a symbol file, and initializes
 360      the struct sym_fns SF in preparation for sym_read().  It is
 361      called every time we read a symbol file for any reason.  */
 362
 363   void (*sym_init) (struct objfile *);
 364
 365   /* sym_read (objfile, symfile_flags) Reads a symbol file into a psymtab
 366      (or possibly a symtab).  OBJFILE is the objfile struct for the
 367      file we are reading.  SYMFILE_FLAGS are the flags passed to
 368      symbol_file_add & co.  */
 369
 370   void (*sym_read) (struct objfile *, int);
 371
 372   /* Read the partial symbols for an objfile.  This may be NULL, in which case
 373      gdb has to check other ways if this objfile has any symbols.  This may
 374      only be non-NULL if the objfile actually does have debuginfo available.
 375      */
 376
 377   void (*sym_read_psymbols) (struct objfile *);
 378
 379   /* Called when we are finished with an objfile.  Should do all
 380      cleanup that is specific to the object file format for the
 381      particular objfile.  */
 382
 383   void (*sym_finish) (struct objfile *);
 384
 385   /* This function produces a file-dependent section_offsets
 386      structure, allocated in the objfile's storage, and based on the
 387      parameter.  The parameter is currently a CORE_ADDR (FIXME!) for
 388      backward compatibility with the higher levels of GDB.  It should
 389      probably be changed to a string, where NULL means the default,
 390      and others are parsed in a file dependent way.  */
 391
 392   void (*sym_offsets) (struct objfile *, const struct section_addr_info *);
 393
 394   /* This function produces a format-independent description of
 395      the segments of ABFD.  Each segment is a unit of the file
 396      which may be relocated independently.  */
 397
 398   struct symfile_segment_data *(*sym_segments) (bfd *abfd);
 399
 400   /* This function should read the linetable from the objfile when
 401      the line table cannot be read while processing the debugging
 402      information.  */
 403
 404   void (*sym_read_linetable) (struct objfile *);
 405
 406   /* Relocate the contents of a debug section SECTP.  The
 407      contents are stored in BUF if it is non-NULL, or returned in a
 408      malloc'd buffer otherwise.  */
 409
 410   bfd_byte *(*sym_relocate) (struct objfile *, asection *sectp, bfd_byte *buf);
 411
 412   /* If non-NULL, this objfile has probe support, and all the probe
 413      functions referred to here will be non-NULL.  */
 414   const struct sym_probe_fns *sym_probe_fns;
 415
 416   /* The "quick" (aka partial) symbol functions for this symbol
 417      reader.  */
 418   const struct quick_symbol_functions *qf;
 419 };
 420
 421 extern struct section_addr_info *
 422   build_section_addr_info_from_objfile (const struct objfile *objfile);
 423
 424 extern void relative_addr_info_to_section_offsets
 425   (struct section_offsets *section_offsets, int num_sections,
 426    const struct section_addr_info *addrs);
 427
 428 extern void addr_info_make_relative (struct section_addr_info *addrs,
 429                                      bfd *abfd);
 430
 431 /* The default version of sym_fns.sym_offsets for readers that don't
 432    do anything special.  */
 433
 434 extern void default_symfile_offsets (struct objfile *objfile,
 435                                      const struct section_addr_info *);
 436
 437 /* The default version of sym_fns.sym_segments for readers that don't
 438    do anything special.  */
 439
 440 extern struct symfile_segment_data *default_symfile_segments (bfd *abfd);
 441
 442 /* The default version of sym_fns.sym_relocate for readers that don't
 443    do anything special.  */
 444
 445 extern bfd_byte *default_symfile_relocate (struct objfile *objfile,
 446                                            asection *sectp, bfd_byte *buf);
 447
 448 extern struct symtab *allocate_symtab (const char *, struct objfile *)
 449   ATTRIBUTE_NONNULL (1);
 450
 451 extern void add_symtab_fns (enum bfd_flavour flavour, const struct sym_fns *);
 452
 453 /* This enum encodes bit-flags passed as ADD_FLAGS parameter to
 454    symbol_file_add, etc.  */
 455
 456 enum symfile_add_flags
 457   {
 458     /* Be chatty about what you are doing.  */
 459     SYMFILE_VERBOSE = 1 << 1,
 460
 461     /* This is the main symbol file (as opposed to symbol file for dynamically
 462        loaded code).  */
 463     SYMFILE_MAINLINE = 1 << 2,
 464
 465     /* Do not call breakpoint_re_set when adding this symbol file.  */
 466     SYMFILE_DEFER_BP_RESET = 1 << 3,
 467
 468     /* Do not immediately read symbols for this file.  By default,
 469        symbols are read when the objfile is created.  */
 470     SYMFILE_NO_READ = 1 << 4
 471   };
 472
 473 extern void new_symfile_objfile (struct objfile *, int);
 474
 475 extern struct objfile *symbol_file_add (const char *, int,
 476                                         struct section_addr_info *, int);
 477
 478 extern struct objfile *symbol_file_add_from_bfd (bfd *, const char *, int,
 479                                                  struct section_addr_info *,
 480                                                  int, struct objfile *parent);
 481
 482 extern void symbol_file_add_separate (bfd *, const char *, int,
 483                                       struct objfile *);
 484
 485 extern char *find_separate_debug_file_by_debuglink (struct objfile *);
 486
 487 /* Create a new section_addr_info, with room for NUM_SECTIONS.  */
 488
 489 extern struct section_addr_info *alloc_section_addr_info (size_t
 490                                                           num_sections);
 491
 492 /* Build (allocate and populate) a section_addr_info struct from an
 493    existing section table.  */
 494
 495 extern struct section_addr_info
 496   *build_section_addr_info_from_section_table (const struct target_section
 497                                                *start,
 498                                                const struct target_section
 499                                                *end);
 500
 501 /* Free all memory allocated by
 502    build_section_addr_info_from_section_table.  */
 503
 504 extern void free_section_addr_info (struct section_addr_info *);
 505
 506
 507                         /*   Variables   */
 508
 509 /* If non-zero, shared library symbols will be added automatically
 510    when the inferior is created, new libraries are loaded, or when
 511    attaching to the inferior.  This is almost always what users will
 512    want to have happen; but for very large programs, the startup time
 513    will be excessive, and so if this is a problem, the user can clear
 514    this flag and then add the shared library symbols as needed.  Note
 515    that there is a potential for confusion, since if the shared
 516    library symbols are not loaded, commands like "info fun" will *not*
 517    report all the functions that are actually present.  */
 518
 519 extern int auto_solib_add;
 520
 521 /* From symfile.c */
 522
 523 extern void set_initial_language (void);
 524
 525 extern void find_lowest_section (bfd *, asection *, void *);
 526
 527 extern bfd *symfile_bfd_open (const char *);
 528
 529 extern bfd *gdb_bfd_open_maybe_remote (const char *);
 530
 531 extern int get_section_index (struct objfile *, char *);
 532
 533 /* Utility functions for overlay sections: */
 534 extern enum overlay_debugging_state
 535 {
 536   ovly_off,
 537   ovly_on,
 538   ovly_auto
 539 } overlay_debugging;
 540 extern int overlay_cache_invalid;
 541
 542 /* Return the "mapped" overlay section containing the PC.  */
 543 extern struct obj_section *find_pc_mapped_section (CORE_ADDR);
 544
 545 /* Return any overlay section containing the PC (even in its LMA
 546    region).  */
 547 extern struct obj_section *find_pc_overlay (CORE_ADDR);
 548
 549 /* Return true if the section is an overlay.  */
 550 extern int section_is_overlay (struct obj_section *);
 551
 552 /* Return true if the overlay section is currently "mapped".  */
 553 extern int section_is_mapped (struct obj_section *);
 554
 555 /* Return true if pc belongs to section's VMA.  */
 556 extern CORE_ADDR pc_in_mapped_range (CORE_ADDR, struct obj_section *);
 557
 558 /* Return true if pc belongs to section's LMA.  */
 559 extern CORE_ADDR pc_in_unmapped_range (CORE_ADDR, struct obj_section *);
 560
 561 /* Map an address from a section's LMA to its VMA.  */
 562 extern CORE_ADDR overlay_mapped_address (CORE_ADDR, struct obj_section *);
 563
 564 /* Map an address from a section's VMA to its LMA.  */
 565 extern CORE_ADDR overlay_unmapped_address (CORE_ADDR, struct obj_section *);
 566
 567 /* Convert an address in an overlay section (force into VMA range).  */
 568 extern CORE_ADDR symbol_overlayed_address (CORE_ADDR, struct obj_section *);
 569
 570 /* Load symbols from a file.  */
 571 extern void symbol_file_add_main (const char *args, int from_tty);
 572
 573 /* Clear GDB symbol tables.  */
 574 extern void symbol_file_clear (int from_tty);
 575
 576 /* Default overlay update function.  */
 577 extern void simple_overlay_update (struct obj_section *);
 578
 579 extern bfd_byte *symfile_relocate_debug_section (struct objfile *, asection *,
 580                                                  bfd_byte *);
 581
 582 extern int symfile_map_offsets_to_segments (bfd *,
 583                                             const struct symfile_segment_data *,
 584                                             struct section_offsets *,
 585                                             int, const CORE_ADDR *);
 586 struct symfile_segment_data *get_symfile_segment_data (bfd *abfd);
 587 void free_symfile_segment_data (struct symfile_segment_data *data);
 588
 589 extern struct cleanup *increment_reading_symtab (void);
 590
 591 /* From dwarf2read.c */
 592
 593 /* Names for a dwarf2 debugging section.  The field NORMAL is the normal
 594    section name (usually from the DWARF standard), while the field COMPRESSED
 595    is the name of compressed sections.  If your object file format doesn't
 596    support compressed sections, the field COMPRESSED can be NULL.  Likewise,
 597    the debugging section is not supported, the field NORMAL can be NULL too.
 598    It doesn't make sense to have a NULL NORMAL field but a non-NULL COMPRESSED
 599    field.  */
 600
 601 struct dwarf2_section_names {
 602   const char *normal;
 603   const char *compressed;
 604 };
 605
 606 /* List of names for dward2 debugging sections.  Also most object file formats
 607    use the standardized (ie ELF) names, some (eg XCOFF) have customized names
 608    due to restrictions.
 609    The table for the standard names is defined in dwarf2read.c.  Please
 610    update all instances of dwarf2_debug_sections if you add a field to this
 611    structure.  It is always safe to use { NULL, NULL } in this case.  */
 612
 613 struct dwarf2_debug_sections {
 614   struct dwarf2_section_names info;
 615   struct dwarf2_section_names abbrev;
 616   struct dwarf2_section_names line;
 617   struct dwarf2_section_names loc;
 618   struct dwarf2_section_names macinfo;
 619   struct dwarf2_section_names macro;
 620   struct dwarf2_section_names str;
 621   struct dwarf2_section_names ranges;
 622   struct dwarf2_section_names types;
 623   struct dwarf2_section_names addr;
 624   struct dwarf2_section_names frame;
 625   struct dwarf2_section_names eh_frame;
 626   struct dwarf2_section_names gdb_index;
 627   /* This field has no meaning, but exists solely to catch changes to
 628      this structure which are not reflected in some instance.  */
 629   int sentinel;
 630 };
 631
 632 extern int dwarf2_has_info (struct objfile *,
 633                             const struct dwarf2_debug_sections *);
 634
 635 /* Dwarf2 sections that can be accessed by dwarf2_get_section_info.  */
 636 enum dwarf2_section_enum {
 637   DWARF2_DEBUG_FRAME,
 638   DWARF2_EH_FRAME
 639 };
 640
 641 extern void dwarf2_get_section_info (struct objfile *,
 642                                      enum dwarf2_section_enum,
 643                                      asection **, const gdb_byte **,
 644                                      bfd_size_type *);
 645
 646 extern int dwarf2_initialize_objfile (struct objfile *);
 647 extern void dwarf2_build_psymtabs (struct objfile *);
 648 extern void dwarf2_build_frame_info (struct objfile *);
 649
 650 void dwarf2_free_objfile (struct objfile *);
 651
 652 /* From mdebugread.c */
 653
 654 extern void mdebug_build_psymtabs (struct objfile *,
 655                                    const struct ecoff_debug_swap *,
 656                                    struct ecoff_debug_info *);
 657
 658 extern void elfmdebug_build_psymtabs (struct objfile *,
 659                                       const struct ecoff_debug_swap *,
 660                                       asection *);
 661
 662 /* From minidebug.c.  */
 663
 664 extern bfd *find_separate_debug_file_in_section (struct objfile *);
 665
 666 #endif /* !defined(SYMFILE_H) */